Search found 2400 matches

by Sunder
Jan 20, 2018 7:19 am
Forum: Battery Technology
Topic: Chilwee lead-graphene battery
Replies: 10
Views: 140

Re: Chilwee lead-graphene battery

amberwolf wrote:
Jan 20, 2018 2:24 am
Archer321 wrote:
Jan 19, 2018 7:25 pm
Gotta have lead.
Rules.
You must live in a really wierd place to require lead-type batteries on your bikes (or other vehicles).
Could be a competition or race?
by Sunder
Jan 19, 2018 10:20 pm
Forum: E-Bike General Discussion
Topic: The winner is . Not what you think
Replies: 18
Views: 469

Re: The winner is . Not what you think

Are you saying the same thing about trains a century ago? Because early steam engines had efficiencies of about 2%; modern gas vehicles approach 40%, and modern EV's approach 90% efficiency (and 50% well to wheels.) Nothing to do with the efficiency of energy conversion. If trains a century ago wer...
by Sunder
Jan 19, 2018 6:50 pm
Forum: Battery Technology
Topic: Chilwee lead-graphene battery
Replies: 10
Views: 140

Re: Chilwee lead-graphene battery

Most sellers are willing to send samples at a higher processing fee.

But unless you must have lead, why go with this, when Lithium batteries of various types out perform on most common characteristics?
by Sunder
Jan 16, 2018 7:31 am
Forum: E-Bike General Discussion
Topic: The winner is . Not what you think
Replies: 18
Views: 469

Re: The winner is . Not what you think

If we were willing to go a bit slower, we could use less massive vehicles and probably have a net gain in safety and use fewer resources. So in that sense, yes, shorter distances would improve things. And lighter slower vehicles are more effective with shorter distances. One day a future generation...
by Sunder
Jan 15, 2018 8:10 pm
Forum: E-Bike General Discussion
Topic: new eZip motor
Replies: 4759
Views: 265678

Re: new eZip motor

OK. Now I got a big question. Scrap metal price for a 2012 PT cruizer is $200. The lady downstairs was scrapping it tommorow as it was towed as it would not go into gear. Either transmission or linkage. I am thinking I might know some friends that can get it running if linkage. not sure about trann...
by Sunder
Jan 11, 2018 6:25 pm
Forum: E-Bike General Discussion
Topic: new eZip motor
Replies: 4759
Views: 265678

Re: new eZip motor

Also I am building a gaming machine for steam games and need a decent video card and 450 or 500 watt power supply. You're seriously tempting me to upgrade. I've had a few unexplained reboots lately, and I can only run games on high detail on 1080p. If I switch to 4K, it only runs on Low-Mid dependi...
by Sunder
Jan 11, 2018 4:28 pm
Forum: Vendor Relations Corner
Topic: Concerns with BMSBattery's Security
Replies: 4
Views: 202

Re: Concerns with BMSBattery's Security

Maybe this borders on paranoid, but I do work in cybersecurity/fraud prevention. Imagine the password you set for BMSB was the same as your email and Paypal password. As Dapuma said, it was automated so no human has seen your password yet. You order a couple high value goods and they're DOA. BMSB be...
by Sunder
Jan 11, 2018 4:16 pm
Forum: Vendor Relations Corner
Topic: Concerns with BMSBattery's Security
Replies: 4
Views: 202

Re: Concerns with BMSBattery's Security

If you recieve a full or partial password, it means your password is not encrypted and visible to admins of the sites as well as any hackers who gain access to the site. Ensure that the password is NOT used for any other account and especially your email. There are criminals out there who have "scan...
by Sunder
Jan 11, 2018 3:14 am
Forum: Battery Technology
Topic: 700 mile charge in 1 minute
Replies: 13
Views: 331

Re: 700 mile charge in 1 minute

Warranty probably says: Battery warranty void if charged above absolute zero.
by Sunder
Jan 11, 2018 3:12 am
Forum: Battery Technology
Topic: MeanWell HLG vs ELG as charger
Replies: 16
Views: 252

Re: MeanWell HLG vs ELG as charger

Yeah. Reading a bit more, it seems even the ELGs hold up under full load on 110v, no derating required. Someone on another forum pointed out that ELGs have a 5 year warranty vs the HLG's 7 year. Also mentioned that each HLG was QA'ed manually, where as ELGs were machine tested. That one I found a bi...
by Sunder
Jan 11, 2018 2:26 am
Forum: Battery Technology
Topic: MeanWell HLG vs ELG as charger
Replies: 16
Views: 252

Re: MeanWell HLG vs ELG as charger

"Derating may be required under low input voltages".

I wouldnt count on the HLG holding up equally on 110v, especially since it also says:

"All parameters [...] measured at 230vac"
by Sunder
Jan 10, 2018 11:50 pm
Forum: Battery Technology
Topic: 700 mile charge in 1 minute
Replies: 13
Views: 331

Re: 700 mile charge in 1 minute

I think the 700 mile in 1 minute is the theoretical "The battery won't catch fire" rate. This newer article here: https://www.express.co.uk/life-style/cars/902345/Fisker-solid-state-electric-car-battery-range-charging-times Says the car should charge 125miles in 9 minutes. I use the reverse measure....
by Sunder
Jan 08, 2018 8:27 pm
Forum: Battery Technology
Topic: Large LiOn from AliExpress?
Replies: 11
Views: 302

Re: Large LiOn from AliExpress?

I recommend OSN power. Many others are dodgy, but these guys have high quality products, good service and nearly the cheapest prices.

If you can't find what you need ask them, and see if they do assembly.
by Sunder
Jan 08, 2018 6:56 am
Forum: Battery Technology
Topic: BMS Battery Alloy Shell Charger Problems
Replies: 597
Views: 40130

Re: BMS Battery Alloy Shell Charger Problems

Have you got the polarity right?

The use a strange reverse connection sensing method, so that when there is no battery connected, it shows the reverse of the expected polarity. its strange and I killed a few fuses that way.
by Sunder
Dec 24, 2017 12:33 am
Forum: Battery Technology
Topic: Speculate what happened to my cells
Replies: 11
Views: 353

Re: Speculate what happened to my cells

2 years, but only in service for 1.
by Sunder
Dec 23, 2017 9:16 pm
Forum: Battery Technology
Topic: Speculate what happened to my cells
Replies: 11
Views: 353

Re: Speculate what happened to my cells

I'm a little lost. 8s 23p = 184 cells, and if you look carefully, one entire 23p row puffed. It's just 4 in the foreground, but you can see more puffed in the back ground.

All cells in the first row puffed, none in the other rows puffed.
by Sunder
Dec 23, 2017 6:59 pm
Forum: Battery Technology
Topic: Speculate what happened to my cells
Replies: 11
Views: 353

Re: Speculate what happened to my cells

It was indeed the positive cell. I wonder why that is. Is there an explanation for that? I've seen chargers in series where the most positive charger seems to do all the voltage saging. Similar problem? As for overheating, what are we talking about? This shed can get to 60*C in summer, but as LiFePo...
by Sunder
Dec 23, 2017 6:27 pm
Forum: Battery Technology
Topic: LTO Lithium Titanium Oxide (Titanate) Battery 30S - Seeking the Ultimate Commuter Battery
Replies: 67
Views: 1766

Re: LTO Lithium Titanium Oxide (Titanate) Battery 30S - Seeking the Ultimate Commuter Battery

I bought from OSN on Alibaba. They bent over backwards to get me the right shipping, and every cell was 5-10% under rated (i.e. every 30ah cell was between 31.5 and almost 33ah.) I would love to place a big order with them at the moment, but since the only use I had for them was an off grid holiday ...
by Sunder
Dec 21, 2017 6:35 pm
Forum: Battery Technology
Topic: LTO Lithium Titanium Oxide (Titanate) Battery 30S - Seeking the Ultimate Commuter Battery
Replies: 67
Views: 1766

Re: LTO Lithium Titanium Oxide (Titanate) Battery 30S - Seeking the Ultimate Commuter Battery

I believe these are either copies, or generics of the same cell. They're certainly in the same packaging: https://www.aliexpress.com/item/Lithium-titanate-battery-2-4V-20AH-LTO-baterie-for-diy-36V-48V-Large-power-gas-electric/32841478461.html?ws_ab_test=searchweb0_0,searchweb201602_1_10152_10065_101...
by Sunder
Dec 19, 2017 5:27 pm
Forum: Battery Technology
Topic: Safe to charge lipo over 4.2 volts if resting voltage under 4.2?
Replies: 3
Views: 168

Re: Safe to charge lipo over 4.2 volts if resting voltage under 4.2?

LiPo doesn't have a concept of a surface charge like Lead Acid, so I wonder if you are really charging over 4.2v per cell, or just seeing it due to resistance, as Billvon said. The reality is, 4.2v/cell isn't a magic number. Its an industry best practice to balance between cycle life and capacity (b...
by Sunder
Dec 18, 2017 7:52 pm
Forum: Battery Technology
Topic: LTO Lithium Titanium Oxide (Titanate) Battery 30S - Seeking the Ultimate Commuter Battery
Replies: 67
Views: 1766

Re: LTO Lithium Titanium Oxide (Titanate) Battery 30S - Seeking the Ultimate Commuter Battery

I have built a 11S LTO battery, but for stationary use only. I have a BMS protected LiFePo4 solar storage battery. It holds a huge amount of energy, but in winter, its power deliver capability can leave something to be desired so I have a 30AH LTO pack which can deliver 300A. Beautiful battery, fit ...
by Sunder
Dec 16, 2017 6:02 pm
Forum: E-Bike General Discussion
Topic: Was looking through aliexpress and...
Replies: 9
Views: 714

Re: Was looking through aliexpress and...

I had 3 disputes with Aliexpress sellers in quick succession. All 3 were solved within 48 hours without Aliexpress getting involved, but they were all under $15. From what I have heard, Aliexpress is trying to attract western buyers, where as they have a flood of Chinese sellers, so tend to side on ...
by Sunder
Dec 12, 2017 5:58 pm
Forum: Battery Technology
Topic: smart BMS - balance charging at partial charges?
Replies: 5
Views: 171

Re: smart BMS - balance charging at partial charges?

You can also get a dumb balancer. It simply daisy chains all cells, detects the highest cell and lowest cell, and sends power between them. Rinse, repeat, until all cells are balanced. Unfortunately, it will do that regardless of the cell voltage, so if left completely unattended, can kill batteries...
by Sunder
Dec 12, 2017 5:52 pm
Forum: Battery Technology
Topic: Super capacitors to save battery life?
Replies: 45
Views: 1292

Re: Super capacitors to save battery life?

This isn't fully relevant, but it is a bit relevant, and I think a bit amusing. My dad used a 11S (24v) LTO pack to charge a 12v battery, unregulated. 1. The 12V battery died, unsurprisingly. 2. The 24v battery "recharged" with some cells at 3.6v, and some cells at 1.8v, so heavy unbalanced (no BMS ...
by Sunder
Dec 11, 2017 5:06 pm
Forum: E-Bike General Discussion
Topic: Car replacement in London/Other Cold Weather
Replies: 9
Views: 443

Re: Car replacement in London/Other Cold Weather

Hmm. So one saying without a car it would be difficult, one saying only 30% of people have cars... I guess living there a few weeks can't hurt and saves an inappropriate bike just sitting there collecting dust in a very small house, if I was wrong. There is always the option of cabs just for a few w...